Handle for rock drills



Patented Oct. 4, 1927.

UNITED 1,644,030 A NT-i; OFFICE. i

WILLIAM PRELLWITZ, or EASTON, rENnsYLvANIA, nssrenonro INGERSOLL-RAND COMPANY,'OF JERSEY CITY,'NEW J'ERSEY,A CORPORATION E NEW JERSEY. .7

HAimLE FOR ROCK DRILLS.

,Application filed Ail st 4 192a SerialtNo; 127,05

This invention relatesto" rock drills, but more particularly to a handle for fluid actuated rock drills of the hand held type.

One object of the inventionis'to cushion the handle of the drill for the purpose-of protecting the operator against the excessive shockand vibration setu in the rock drill during its operation i Other objects will appear hereinafter.

10 v The invention consistsof the. combination of elements, features of construction and-arrangement of parts, substantiallyas hereinafter described and more rparticularly pointed out in the appended claims and i llustrated in the accompanying drawings, in

which f Figure 1 isan elevation of a rock drill equipped with a handle constructed 1n accordance with the practiceof the invention,

the handle and the back head being, shown in section,

Figure 2 is transverse view partly in section taken through Figure 1 on the line 22looking in the direction of the arrows,

and

Figure 3 is a side elevation of the back head and a portion of the handle.

Referring to the drawings, the invention 1s shown embodied in a rock drill of the hand held type in which a cylinder A, a front head B and a back head C are held in.

assembled relationship with respect to each other by suitable spring pressedvside bolts D. A steel retainer E supported by trunnions F formed on the front head B partly encircles a drill steel G in the front head B forwardly of a collar H wherewith it cooperates for preventing ejection of the drill steel from the front head. A valve chest J is in this instance bolted to the cylinder A to accommodate a distributing valve (not shown) whereby the distribution of pressure fluid to the ends of the cylinder A for reciprocating the hammer piston (not shown) is effected.

In accordance with the present invention, a pair of diametrically opposed lateral pr0- jections K are formed on the back head C and have suitable apertures K for the re- 0 ception of the side bolts D. The bottom faces L of the projections K act as abutments for inwardly extending hooks 0 formed on extensions P. The extensions P in this instance are of flat rectangular cross sectional area and are provided with holes Q at their upper or rearward-ends for'the reception of a bolt'R. This bolt R is of sufficient length to extend well on opposite sides of the extensions 0 and is provided at its ends with grip portions S, which comprise the. handle for manipulating the rock drill, A nut' T screwed on the bolt, R

back headC and the handle. To this end a serves to clamp the grips Sand the. exten- A body portion U' is mounted on'the bolt R between the extensions]? thus acting as a spacer for the extensions and has 'a pair of integral guide arms vV at each end which extending. downwardly to cooperate s'lidably with the sides of the projections K. .The guide arms V are preferably so positioned that during'ithe normal operation of the drill they will be held out of contact with the back head 0. i

In order to cushion the movement of the handle and thus protect the operator against excessive vibration set up in the rock drill during its operation, a plurality of springs W are interposed between the handle and the back head to abut with one end a flange X formed integrally with the member U and with their other ends the back head C. In the present instance sockets or depressions Y are formed inthe rearward face'of the back head G to receive one end of the springs and similar sockets Z are formed in In order to-obtain an adequate cushioning effect a relatively large number of springs are employed, SlX springs being shown in the present instance. The springs are preferablyequally spaced on a large circle concentric with the longitudinal axis of the back head to prevent the handle from tip; ping with respect to the drill when reater pressure is ap lied to one end of the acidic than to the ot er,

This is a preferred construction,

The foregoing desoribed invention has been'found'to b'unu'silally efiicie nt in opera tion. Owing to the large number-of light springs emp oyed e n le is a al t mes adequa e y "cushioned o prevent he rans: mission of shock thereto. These springs,

howeveri are of sufiioient strength to hold the han le normally firmly in retracted position so that when the rock drill'is being used tea p y ng p r eses he h ndle i l e held against toofree movement with respect to the leck dri Ano her es ab e featu of resent invention that there are no rigi c iie'oti'oiihetiveen the rook'drill and han'dle'and tliere are therefore no parts siibjeeted to undue strains when "gre: ter

pressti're is appliedto end olthe handle than to'the'o't'lie'r end I I claim: I

'a'fluid actuated rock drill, a back head,'laterajl projections on the h'aoli'heacha han dlej foir the drill havinga body portion, extensions separate fronrthe body -portion earr'iedh'y the handle; hooks on the e xtension torooperat'e 'With "the" projections for liiniting rearward movement of "the handle W th s ct 'e lee heed, guide e i n' I jeotions or preventing relative rotation beheadflateral projections at each side of the the handle inte r al With the body portion to cooperate slida 1y 'With the sides of the pro- 30 tween; h'ehandh nd thehank heed, and pri gs f r eueli enin th h edleieml 11 ing said handle in a normally retracted .po siti'on. I v

2. In a fluid actuated rock drill, a back back head having apertures, side bolts in the apertfireidforseehrin the ba okheadto the cylinder qffth rook drill, a handleiextensions oarifieclhy'the handle, andflyiffg posite the en ds fof the: 'aidlateral projeotions inwardly extending hookson theextensiofis to cooperate,iritli'the prejectie is fordi friit' ing upw i ai'd movement of the haiidle with respeet to the hack head fdo'iini'viti dly extend- 

